Tubing hangers, tree caps, casing hangers, and other pressure controlling and remotely delivered tubular assemblies used in the oil and gas industry have sealing assemblies used to direct the flow of produced fluids as well as injected and hydraulic control fluids. These seal assemblies cannot be fully supported on each end as radial clearances between the supporting hardware and the seal bores must be present to allow assembly or remote delivery of the interfacing parts.
Plastic rings, known as extrusion resistors, are typically assembled with a tight or interference fit to minimize the clearances between the hardware and prevent flow of non-metallic seal elements into small gaps between the hardware and seal bores. As pressure and temperatures increase, the gaps created due to thermal and mechanical deflections increase and the stiffness and strength of the plastic material decrease.
When pressure is applied to typical seal carriers, the seals are crushed into a groove and the metal of the typical seal carrier does not follow the deflections induced by pressure, thereby allowing the seal out of the grove.
A need exists for a device to replace known extrusion resistors with a pressure actuated seal carrier that allows no gap between the hardware and seal bores at all pressures and temperatures. The pressure actuated seal carrier deflects under pressure a greater amount than the surrounding seal bores insuring contact between the metal carrier and seal bores as pressure increases.
A need exists for non metallic sealing elements to be used in high temperature and high pressure sealing applications.
A need exists for a seal carrier assembly operable for effecting a seal between a pair of spaced surfaces with no extrusion gap at all pressures and temperatures.
The embodied devices herein were designed to satisfy these needs.